Operation Tanne Ost was a German operation during World War II

World War II

World War II, or the Second World War , was a global conflict lasting from 1939 to 1945, involving most of the world's nations—including all of the great powers—eventually forming two opposing military alliances: the Allies and the Axis...

 to capture the island Suursaari (Swedish Hogland, Russian Gogland) in the Gulf of Finland

Gulf of Finland

The Gulf of Finland is the easternmost arm of the Baltic Sea. It extends between Finland and Estonia all the way to Saint Petersburg in Russia, where the river Neva drains into it. Other major cities around the gulf include Helsinki and Tallinn...

 before it could fall into Soviet

Soviet Union

The Soviet Union , officially the Union of Soviet Socialist Republics , was a constitutionally socialist state that existed in Eurasia between 1922 and 1991....

 hands. Suursaari was especially important because it worked as a lock in the Finnish Gulf guarding the minefields keeping the Soviet Baltic Fleet in Kronstadt

Kronstadt

Kronstadt , also spelled Kronshtadt, Cronstadt |crown]]" and Stadt for "city"); is a municipal town in Kronshtadtsky District of the federal city of St. Petersburg, Russia, located on Kotlin Island, west of Saint Petersburg proper near the head of the Gulf of Finland. Population: It is also...

.

The operation was initially planned with another operation to capture the Åland Islands

Åland Islands

The Åland Islands form an archipelago in the Baltic Sea. They are situated at the entrance to the Gulf of Bothnia and form an autonomous, demilitarised, monolingually Swedish-speaking region of Finland...

 (Tanne West), which was not carried out.

On September 15, 1944, a first wave of 1400 men from both the Wehrmacht

Wehrmacht

The Wehrmacht – from , to defend and , the might/power) were the unified armed forces of Nazi Germany from 1935 to 1945. It consisted of the Heer , the Kriegsmarine and the Luftwaffe .-Origin and use of the term:...

 and the Kriegsmarine

Kriegsmarine

The Kriegsmarine was the name of the German Navy during the Nazi regime . It superseded the Kaiserliche Marine of World War I and the post-war Reichsmarine. The Kriegsmarine was one of three official branches of the Wehrmacht, the unified armed forces of Nazi Germany.The Kriegsmarine grew rapidly...

 were loaded on ships in Tallinn

Tallinn

Tallinn is the capital and largest city of Estonia. It occupies an area of with a population of 414,940. It is situated on the northern coast of the country, on the banks of the Gulf of Finland, south of Helsinki, east of Stockholm and west of Saint Petersburg. Tallinn's Old Town is in the list...

. Before the assault the German commander tried to negotiate with the Finnish commander on Suursaari, as he thought the Finns might leave without resistance. The negotiations were a complete failure and the invasion had to begin. When the German ships approached Suursaari the Finnish crew on the island opened fire. However most of the troops made it to the beaches, but there the difficulties continued, somewhat because of the Finnish defense being much more numerous than expected. Two Finnish patrol boats were trapped in Suurkylä harbor and sunk. After sunrise the Soviets made bombing runs on the German ships and later bombed both German and Finnish positions in the island. A second wave of troops was withdrawn before they could land. Finnish Navy motor torpedo boats sank several German vessels. After that German ships decided to leave because they failed to make radio connection to the landed troops. The operation ended in a complete failure, with the Finns capturing 1,231 German prisoner

Prisoner of war

A prisoner of war or enemy prisoner of war is a person, whether civilian or combatant, who is held in custody by an enemy power during or immediately after an armed conflict...

s.

Soviet Air Force made three attacks against German positions and ships. The attacks also caused some Finnish casualties. Germans didn't let the heavy cruiser

Heavy cruiser

The heavy cruiser was a type of cruiser, a naval warship designed for long range, high speed and an armament of naval guns roughly 203mm calibre . The heavy cruiser can be seen as a lineage of ship design from 1915 until 1945, although the term 'heavy cruiser' only came into formal use in 1930...

 Prinz Eugen

German cruiser Prinz Eugen

Prinz Eugen was an Admiral Hipper-class heavy cruiser, the third member of the class of five vessels. She served with the German Kriegsmarine during World War II. The ship was laid down in April 1936 and launched August 1938; Prinz Eugen entered service after the outbreak of war, in August 1940...

 support the invasion, as Soviet air threat in the area was shown by these attacks.

This operation marked the beginning of hostility between German and Finnish troops, known as the Lapland War

Lapland War

The Lapland War were the hostilities between Finland and Nazi Germany between September 1944 and April 1945, fought in Finland's northernmost Lapland Province. While the Finns saw this as a separate conflict much like the Continuation War, German forces considered their actions to be part of the...

. Before this, the Germans had conducted their withdrawal from Northern Finland without incident.

Finnish order of battle

Finnish forces consisted of Coastal Artillery Regiment 12 (RTR 12). Defence was organized into four sections as follows.

Northern section, 1st Battalion (strength 340 men)

• 10th Coastal Defence Company
• 1st Section/201st Light Artillery Battery
• 24th Heavy AA-Battery
• 5th Light Coastal AA-Battery
• 1st Platoon/Heavy mortar Company

Mountain section, 2nd Battalion (strength 475 men)

• HQ-Company/Coastal Artillery Regiment 12
• Section/9th Motorised Heavy Artillery Battery
• 2nd Platoon/Heavy Mortar Company
• 1st Platoon/1st Coastal Engineer Company
• 8th Coastal Defence Company

Middle section, Coastal Infantry Battalion 7 (strength 295 men)

• 7th Coastal Defence Company
• 9th Coastal Defence Company
• 34th Heavy AA-Battery
• Training Company

Southern section, 3rd Battalion (strength 418 men)

• 2nd Company/Coastal Battalion 7
• 3rd Company/Coastal Battalion 7
• 3rd Platoon/Heavy Mortar Company
• 2nd Section/201st Light Artillery Battery

See also: List of military operations